Colloidal suspensions such as cementitious suspensions, sewage, muds, paints, ... are yield-stress fluids which display a time-dependent behavior. Their peculiar behavior comes from the ability of the particles to flocculate at rest and under shear. The flocculated particles can also be redispersed, at least partly, by shearing or by agitation. Knowledge of the structure of flocculated materials and of the physical processes which govern this structure is necessary for understanding their flow behavior. Such knowledge is also a key for developing models and for industrial applications.

Objectives

The aim of the workshop is to present recent advances in the field of flocculated suspensions obtained with complementary advanced tools (direct visualization of 2D-model systems ; confocal microscopy ; neutron scattering ; microrheology ; numerical simulation ; homogenization approaches...). Studying the mechanical behavior of individual flocs and measuring the structural properties of sheared flocculated suspensions are indeed key elements that should be used to validate numerical approaches and to predict their rheological behavior in micromechanical approaches.
Applications and open questions in the field of fresh cementitious materials, for which admixtures, mixing process and shearing history among others influence the flocculation level and thus the material workability, will also be presented.
The workshop offers the opportunity to bring researchers and engineers together so as to combine the skills of both fundamental research and technical matters solving.